Offering some basic "KNOWLEDGE" for what it is worth.
Jupiter rules expansion, enlargement, along with other attributes. The growth of Cancer cells is unbridled and "runaway" in nature, growing without limitations.
Many Cancers are the end result of the body not being able to consistently rid itself of wastes --- often wastes associated with eating and digestion, but this can also be wastes in the blood, lymphatic and breathing systems. Bad eating habits, working conditions, sleep patterns, and weight management issues can all affect the body's processes in a regular manner. Therefore it is necessary to both review each planet in your chart relative to what it rules or symbolizes as well as to objectively look at anything in your life that contributes to you looking and acting different from the "average" person you see around you and on TV.
One place to start understanding effects that can affect the physical body is to look at the planets 1) in terms of their medical associations, and 2) when they are in conjunction, and 3) when in square or opposition. The signs ruled by those planets in harsh aspect to each other will often point to the site of a Cancer or other physical problem.
** Each planet has specific body functions that it relates to.
** Conjunctions amplify and focus the planet's symbolic associations, hence they can promote excessive actions or practices in your life.
** Squares and oppositions can point to various stresses. The associated planets will indicate what these stresses might express themselves like.
** Signs ruled by stressed planets can indicate the symptom ares of any "dis-ease" to show up at.
Sun and Moon patterns give an overall picture of health. Stress is often seen with Moon-Pluto-and (Mercury or Saturn) combinations, but any afflicted Moon can produce stress. Mercury (since it rules two common signs) can create or instigate problems with other hard-aspected planets. When the common signs (Gemini, Virgo, Sagittarius, Pisces) are on the angles they suggest a more inactive or less focused person (other indicators not being noted) which can contribute to less exercise, focus and activity as well as a lack of self-control and a purposeful life.
You can find sources that will tell you that certain sign-degree positions mean a proclivity to one thing or another. I can't comment on those. But the above simple guidelines should get you started. Dave
Some sources